Project Summary Emerging data has identified the enteric nervous system (ENS) as a key regulator of intestinal barrier functions. Besides the control of peristaltic movements, gastrointestinal blood flow and secretions, the ENS has been shown to reinforce the intestinal epithelial barrier (IEB) and modulate intestinal permeability. Changes in ENS have largely been described in gastrointestinal diseases with altered IEB functions. However, the link between the molecular and cellular effects of the ENS on IEB lesions still remains elusive mainly due to the lack of models. In this context, the development of human intestine with an ENS represents a real opportunity to expand our knowledge into the effect of ENS on intestinal development and toward the understanding of pathophysiological processes leading to digestive diseases. Our recently developed methods to generate a functional human intestine, combined with unique transplantation models, provide a novel and ideal experimental approach. Building on this previous model, we generated a complex human intestine reassembling the ENS features to test the hypothesis that human ENS regulates intestinal development, growth, and maturation. This grant application brings another level of innovation to the GI organoid systems by tissue engineering in the enteric nervous system. This proposal has three major strands. Precisely, we will define the ENS mechanisms underlying human intestinal organoid development into a fully laminated and functional mature intestine (Aim 1). We will determine the influence of intestinal luminal contents on the ENS phenotype and its associated functions (Aim 2). Finally, we will characterize the impact of congenital defective ENS on the intestinal development that lead to gastrointestinal dysfunctions (Aim 3). This research plan will allow for unprecedented studies in the future of the molecular basis of human ENS control of GI functions and diseases. To successfully achieve the aforementioned goals, a multidisciplinary group of mentors, collaborators and consultants will provide guidance in the research strategy and other training areas such as grant writing, personal, technical and management skills. Additionally, I will get additional training and course work to succeed in the completion of the proposal and in my transition toward a successful independent scientific career. Mentors Pr Michael A. Helmrath, MD, MS - Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA Pr James M. Wells, PhD, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA Collaborator Dr Michel Neunlist, PhD - National Institute of Health and Medical Research (INSERM) ? Unit 913 Neuropathies of the Enteric Nervous System and Digestive Diseases, Nantes, France Consultants Pr. Marshall H. Montrose, PhD ? University of Cincinnati, Cincinnati, OH, USA Dr. Ajay Kaul, MD - Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA Dr. Noah F. Shroyer, PhD ? Baylor College of Medicine, Houston, TX, USA Referees Dr. Sean R. Moore, MD, MS - Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA Dr. Jason Spence, PhD - University of Michigan Medical School, - Ann Harbor, MI, USA Dr. Yana Zavros, PhD - University of Cincinnati - Cincinnati, OH, USA